Dinelti Fitria, Lufri, L., Elizar, E. and Ali Amran 2023. 21st Century Skill-Based Learning (Teacher Problems In Applying 21st Century Skills). International Journal Of Humanities Education and Social Sciences. 2, 4 (Feb. 2023). DOI:https://doi.org/10.55227/ijhess.v2i4.409.